I want to use crude extract ( seed powder ) to treat animals, is it necessary to go for GC-MS for this extract or should i have to use aqueous or methanol extract for this study
I assume that this test is generally accepted (preferably validated) as a valuable test for antioxidant performance. The drawback of any biological test is the rather large variability in results. Chemical test are generally more precise.
If you do not know what compound you are looking for, GC-MS or any analytical technique is a waste of time and money. So still - in my opinion - many questions to be adressed before an advise can be given.
Usually mutiple extracts should be used, not only aqueous or methanol extracs. Different ration of aqueous and methanol extracts should be used. If neccessary GCMS or others will be used to analyze its components.